Abstract In order to observe the relationships between the temporal variations of CO2 surface fluxes and the CO2 soil gas transport in soil profile before and during rainfall events, two experiments were conducted in a controlled natural environment at different time periods. These experiments consisted in injecting pure CO2 in a lysimeter at 160 cm depth and simulating heavy rainfall event at its surface for 2 weeks. During the whole experiments, CO2 soil gas concentrations and surface fluxes were continuously monitored. These measurements showed that the flux measured through the flux chamber were consistent with the concentration profiles. During simulated rainfall events, the concentrations and fluxes showed a clear change linked to the presence of water on the top of the water profile. The results clearly show a significant decrease of CO2 flux to atmosphere induced by rainfall infiltration and consequential wash-out of the CO2 present in the soil.

中文翻译：

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土壤二氧化碳流入大气：降雨对 CO2 传输的作用

摘要 为了观察降雨事件前后土壤剖面中CO2表面通量的时间变化与CO2土壤气体输送之间的关系，在不同时间段的受控自然环境中进行了两个实验。这些实验包括在 160 厘米深度的蒸渗仪中注入纯 CO2，并在其表面模拟强降雨事件 2 周。在整个实验过程中，持续监测 CO2 土壤气体浓度和地表通量。这些测量表明通过通量室测量的通量与浓度分布一致。在模拟降雨事件期间，浓度和通量显示出与水剖面顶部存在水有关的明显变化。